In a mobile communication system, an RF (radio frequency) block is designed to support various frequency bands. In particular, a variable capacitor having variable capacitance values with respect to each frequency band must be used as a capacitor for a filter directly related to the frequency band.
In addition, among components of the RF block, a voltage controlled oscillator (VCO) adjusts voltage applied to the variable capacitor to obtained variable capacitance, thereby changing the resonant frequency. The variable capacitor is a very important device for a tunable filter and the VCO of the RF block.
However, in the case of a tuner module circuit including the variable capacitor, the construction or specification of the devices may vary depending on manufacturers, causing the inefficiency of the suppliers and customers.